Pneumatic piano



,W; G. BETZ.

I PNEUMATIC PIANO. APPLICATION nun luv. 1a, 1009.

Patented Jan. 3,1911.

WITNESSES.- Vfihyf, a",

ATTORNEY.

UNITED STATES PATENT onnrcE;

WILLIAM G. IBETZ, OF STEGER. ILLINOIS, ASSIGNOR TO STEGER & SONS PIANOMANU- FACTURING COMPANY, OF CHICAGO, ILLINOIS is CORPORATION OFILLINOIS.

PNEUMATIC rinse Specification of Letters I'a tent. Application filedNovember 18, 1909.

Patented Jan. 3, 1911. Serial No. saaesa.

To all 'it'may concern: 1

.Be it known that I, WILLIAM G. Bnrz, of

' Steger, county of Cook, and State. of Illinols, have invented acertain new and use-. ful Pneumatic Piano; and I do hereby declare that'the followinglis a full, clear, and exact description thereof,reference being bad to the accompanying drawings.

The object of-this invention consists in providing the individualpneumatic elements of a neumatic piano with a vertically disposedsecondary valve held by a spring which retracts as the valve moves to anopen Said spring is preferably insert-ible and. held in a metallic plateso that it is accessible and readily removable. This renders the springand valvereadily accessibleand removable, so that the valve will neverget out of order or act-sluggish, but the'chief advantage is the veryrapid vibratory movement of the valve that 3.; possible with thisconstruction.

The nature of the invention will be understood from the accompanyingdrawings and the following description and claims.

In the drawings Figure l is a central vertical section through apneumatic element and associated parts; some, parts being broken away.Fig. 2 is a section on the line 2--2 of Fig. '1. Fig. 3 is a sectionlike what shown in the right-hand part of Fig. 1 with the secondaryvalve open instead of closed, and the other parts in their position whenthe machine is not in operation.

In the drawings herein 10 represents the key of a iano-forte having acapstan screw ll extent ing upwardly therefrom, which is engaged by asticker 12 that is pivoted at its upper end to a wippen, which actuatesthe piano hammer. The sticker 12 1s actuated by thclerer that isfulcrumed between itsv ends to the lower end of the 'bar 21, whichextends-i down from the cross bar 42. One

' end of said ever actuates the sticker through plat'e to the chamber31between the metal plate 32 and the wall 33. This wall has an opening orport 34 through it which is closed by a secondary valve 35, supported bya helical-spring 36. The spring tends to open' the valve. The apex ofthe helical spring is secured to and carries the valve 35, while theother end of the spring rests in an annular seat 37 in the plate Theplate 32 is secured by screws 38 tofthe parts 39, so that by removingsaid screws the plate 82, spring-36 and valve can be readily withdrawn.The port 34 brings the cham ber 31 111 communication with the chamber 40which lies between the wall 33 and the end wall ofcasing 41. The casing41 rests upon the bottom 22 and it has secured upon its top a plate 43.Said plate 43 is also secured upon the part 89, see Fig. l and thepartition plate 32, so as to form a valve chamber at one end andabellows chamber at the other'end. The chamber 40 communicates' througha passageway 45, shown by dotted lines in Fig. 1 and full linesin Fig.

2, with a suction chamber 46 that is formed by the .plate 47 and pieces48 and 49 and the plate 43. Above the plate 47 there is an open airchamber 50 and the port 51 leads therefrom to a passageway 52 in saidplate 47 that communicates withlthe passageway 53 leading therefrom intothe wall 41" and in communication with the pouch 54 that carries a pin55 thatbears against the secondary valve 35 to push said valve open,when external air enters the passageway 53.. Then the-air will bewithdrawn from the bellows through the suction chambers 40 and 46, whichare in communication with some suitable air exhausting means not shown.p

The air for actuating the pouch 54 is .admitted through the port 51 bythe primary valve 60, which closes said port 51 normally. This valve isopened by air coming through the tracker board, not shown, by way of thepassageway (31 to a point beneath the pouch 62, so that when the openingin the tracker board is exposed for the admission of air, it will enterthe passageway 61 and qevate the pouch 62 to op'enthevalve a d let airinto the passagewa to actuate he pouch 54 to open the va ve 35 to permitthe exhaust of air from the bellows 27 a and therelot:

by actuate the-lever 2Qandoperate the sticker 1.2.

There is a bleed holej70 througliitho plate '43 and incommunicationjjwithvfthejsuction chamber in H some me no G in thetracker hoard pass my 61, so that when the tracker board or thenwsagcrmy 61 is closed the air then bleed hole into the suction chamberand that. permits the pouclrGfZ to descendso that the valve closes theport 51.- Then the pressure of the air in the passageway diminishes theair from the passageway is drawn into the suction chamber someWhatthrough the port having the stern of the valve-(i0 extending throughit which permits the pouch aim return from the ectuzitcc position to theposition shown in, The suction through the 'l and 3.

'il cuuse atmospheric pressure to "'e against the action of the spring38, but this ettect is diminished by the pull. of the i so that wliiensir enters the pcsssgehu 53 and act-notes the pouch pin 56 readilypushes the valve to the en position, which is the 0 on of the valveshown in Fig. 3, but in. Fig. the pouch and pin have returned'to theirinoperative position.

ivhen the device is idle the parts are in the position shown in -Fig.thespring 36 holding the valve 35 open. When the 'device isin usesuction through port 3 k and chamber e0 normally holdsthe valve 35closed, as shown in Fig. l, in spite of the pull or" the spring 36. Whenair enters the tracker hoard slot and passageway 61, it :ictuates thepouch 54-. so that the pin will push the valve 35 open in spite of thesuction which tends to close it, and then suction will draw the air outof the he'lows actuate the lever and In this operation of opening thevalve the sac-34w b end 1 spring 36 cooperates with the pin 5650 as tolessen the task ot the znr-pushed p n 56,

rendering the device sensitive. 1" in will be somewhat Withdrawn throughthe What claim csniy invention and desire "to secure by Letters Patent5:

element including {1 mire/ a retrectilo spring secured at its endcentrullf to said. valve and tending to hold the. vavve open, and :1ren'ioveble plate provided with. an openins with a grooved wall in whichthe other end of said spring is seated, substantially as set forth. r

In a. pneunmtie piano, a pneumatic element including a vaivc, a 5 ringfor supporting said valve which ten s to hold it in an open position, apouch aida ted to be'acted upon by air pressure, an a pin extending fromthe pouch toward said Valve. for cooperating with the spring in openingthe valve when the pouch is actuated.

In a pneumatic piano, a pneumatic element including a be lows, meanshaving suction passageway therefrom through a suction port, a valve forclosing saidsuction port, a spring for supporting andtendin to hold saidvalve in open position and adapted to yield during the closing thereof,it pouch, a said valve or opening t e same. andmeans for conveying airunder atmospheric presin extendin from the pouch to

